Sisi’s sister Néné is engaged to Emperor Franz Joseph. Against her will, Sisi travels to Bad Ischl where the engagement is made official, yet there’s an undeniable connection between Sisi and Franz.

The consummation of the wedding turns out to be a damp squib, but the Emperor shows his affection for Sisi by pretending to his mother, the strict Archduchess Sophie, that it’s all gone smoothly.

Barely recovered from his injuries, Franz hurries back to his troops, hungry for revenge. The war is an unmitigated disaster for Austria; Napoleon III seems to have won the upper hand.

Sisi and Franz travel back to Vienna after a tragedy, where they are met by Sisi’s family, who have come to offer their support.

To prevent a new war in Europe, Sisi and Franz must travel to France to ask Napoleon III for help. However, it is not only their old enemy that causes them concern, but also an unexpected reunion.

At Count Andrassy's country estate, Sisi is reminded of the carefree freedom of her childhood, and his considerate nature puts the Empress more and more under his spell.